MMTTY Text to Speech


   This article is for amateur radio operators who want to use a screen reader to read text messages received by the MMTTY digital modem program. A separate article describes the accessibility of the MMTTY operating controls for blind and vision impaired hams.

Problems With Dynamic Text

   Text that streams into the Received Text Window of a digital modem program causes two problems for screen readers:

   First, if the reader processes a line of text that is still streaming, it reads part of the line and stops. To hear the rest of the line, you have to start at the beginning.

   Second, when the text box display window is full, lines scroll up as new lines arrive. By the time a new line has been read, there may be no indication of which line to read next.

Reading TTY Text

   Short transmissions, as in RTTY contests and RTTY DXing, make it possible to work around these problems. The following examples demonstrate how to use a screen reader with MMTTY text. The commands are for JAWS, but the same methods can be used with other screen readers. MINUS, DOWN ARROW, and UP ARROW indicate keys in the keyboard number pad.

Using the Mouse Control Keys

   1.  To position the JAWS cursor, open MMTTY and press INSERT-MINUS. This routes the cursor to the upper left corner of the text box.

   2.  While listening to the received audio, tune to an RTTY signal using the VFO knob on the radio. Enabling AFC in MMTTY makes tuning easier.

   3.  When the transmission stops, press INSERT-UP ARROW to read the first line of text. At the end of the line JAWS reads "Group box."

   4.  After the next message is in, DOWN ARROW moves the cursor down one line and reads it. At the end of each line JAWS reads "Group box."

   If JAWS gets close to a word that is still being decoded, it reads "Group box scroll-down symbol," and stops reading. Press INSERT-UP ARROW to read the entire line after the transmission stops.

   When the signal to noise level is low, noise characters, called "hash," may make reading difficult. In that case, you can spell a line one character at a time using INSERT-UP ARROW twice, quickly.

Scrolling Lines

   Each new message is displayed under the previous one. Messages accumulate, and eventually they are displayed on the bottom line of the window. The previous lines all scroll up to make room. The bottom line is easy to identify, because DOWN ARROW reads "Clear," the label on a macro button under the window.

   There are two ways to approach this change in the way text is displayed:

   One is to prevent it by clearing the window after each QSO. You can assign a keyboard shortcut for that (Edit Menu → Assign Shortcut Keys).

   The other approach is to leave the cursor on the bottom line and read each message with INSERT-UP ARROW. The JAWS cursor stays at the location in the window where you put it, even when lines are scrolling. If a line of text scrolls up while it is being read, JAWS continues to read it, but the cursor does not relocate. After the line has been read, pressing INSERT-UP ARROW reads the next transmission.

   Random noise characters ("hash") and carriage returns may cause a line of text to scroll up before you can start reading it. In that case, UP ARROW will find it.


   Transmitting does not change the location of the JAWS cursor. For example, after you type in the Transmitted Text Window or use keyboard shortcuts to launch macros, the JAWS cursor remains in position to read the next message.

For More Information

   MMTTY Accessibility.


   RTTY transmissions during contests and DXing are short. This makes it practical to use a screen reader to read text received with MMTTY.


   Thanks to Bob, K3UL, for pointing out that MMTTY text is accessible via screen reader mouse control keys. Also thanks to Brian, W1BLS, for his generous help.

Author Information

   Peter DeNeef, AE7PD, is an Extra Class amateur radio operator in the U.S. This Web site has no ads or conflicts of interest.
Email:  HamRadioAndVision "at" gmail "dot" com.

rev. 11/5/2012

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